Method to operate through a telephone line one automatic phone answering equipment specified among a plurality, and apparatus to carry it out
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Method and apparatus for controlling a subscriber phone system including at least one automatic phone-answering machine
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Method for completing the connection between a telephone exchange and the phone subscriber's line in response to the reception, at the exchange, of a pre-established code
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Method and apparatus for processing coded information received through a telephone line during the inter-ringing periods
